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The identification of lattice multiphases in TiO2 nanocrystals is studied by high resolution transmission electron microscope and electron diffraction patterns. Based on the spectroscopic analysis using soft x-ray absorption and resonant inelastic soft x-ray scattering, it is believed that the oxygen vacancies at the interface exhibit structural distortion of the TiO68−cluster around the defect site as for the multiphase lattice. We elucidate that the extra 3d electrons nearby induce the inelastic scattering features with the excitation energy dependence owing to different energy relaxation processes, a characteristic of the electron-phonon coupling or the nature of the electron-hole pair at the intermediate state. The manifold dd excitations driven by the strong interaction between Ti-3d and O-2p electrons are noticeably rich, coexisting on both Ti and O sites. This sophisticated experiment can advance the perspective of nanocomposite TiO2 for various interactions of surface Ti3+ in applications of future devices.

With flexibility in tuning their electric and magnetic properties, multiferroics can be used in information exchange and storage in ways that are very different from the present electronic materials. Here we use resonant soft X-ray scattering spectroscopy to study the F-type (0,τ,0) and C-type (0, 1–2τ, 0) diffraction peaks from sinusoidal antiferromagnetic spin order in multiferroic DyMnO3. By comparing the temperature dependence of ordering wave vectors τ, peak intensities I, and correlation lengths λ measured at Mn L2-, O K-, and Dy M5-edges, we show that the nearly perfect locking between the ordering wave vectors from Dy 4f states and Mn 3d orbitals manifesting the second harmonic diffraction peak implies the notable orbital involvement in the coupling between Mn and Dy spins. Our DFT calculations further suggest that the lattice response to different antiferromagnetic ground states (A-type versus E-type) is much weaker in TbMnO3, in agreement with previous claim that the symmetric exchange interaction can be an important factor for understanding the ferroelectricity in DyMnO3 than in TbMnO3.

Solid polymer electrolytes (SPEs) show tremendous potential for solid-state lithium metal batteries; however, challenges such as low ionic conductivity and poor mechanical strength hinder their progress. This study integrates Fe-MIL-101 metal organic framework into a poly(vinylidene fluoride-co-hexafluoro propylene) (PVdF-HFP)-based SPE system to address these limitations. The integration of Fe-MIL-101 offers two critical benefits: (1) interaction of inorganic Fe3+ metal centers with PVdF-HFP enables fast Li+ transport by increasing free Li+ availability in the system through Lewis acid–base interactions. (2) Fe-MIL-101 significantly improves the mechanical strength of the SPE, boosting its structural integrity. Fe-MIL-101-integrated SPE enables excellent room temperature cycling stability in solid-state Li‖LiFePO4 (LFP) full cells, retaining ∼91% capacity after 300 cycles and ∼89% capacity after 400 cycles at 0.2 C. Advanced characteristic techniques such as synchrotron-based in situ X-ray diffraction and X-ray absorption spectroscopy were employed to explore structural evolutions in the LFP cathode and the Fe-MIL-101-integrated SPE during cycling. Furthermore, improved room temperature electrochemical performance is demonstrated in solid-state Li‖LiNi0.6Mn0.2Co0.2O2 (NMC622) batteries with Fe-MIL-101-integrated SPE, retaining 91.4% capacity after 175 cycles at 0.1 C. This work highlights the effectiveness of Fe-MIL-101 in enhancing the SPE properties, paving the way for the advancement of high-performance solid-state lithium metal batteries. [ABSTRACT FROM AUTHOR]

The development of effective and stable non‐precious catalysts for hydrogenation of ester to diols remains a challenge. Herein, the catalytic hydrogenation of ethyl lactate (EL) to 1,2‐propanediol (1,2‐PDO) with supported Co catalysts derived from layered double hydroxides (LDHs) is investigated. Catalytic tests reveal that LDH‐derived Co catalysts exhibit the best catalytic performance with 98 % of EL conversion and >99 % of 1,2‐PDO selectivity at mild conditions, compared with other Co catalysts (supported on Al2O3, and TiO2) and LDH‐derived Cu catalysts. Due to the strong interaction among Co and Al matrix, the main composition is metallic Co0 and CoO after reduction at 600 °C. Besides, the catalyst shows good recyclability in the liquid phase hydrogenation. The superior catalytic performance can be attributed to the synergistic effect between Co0 and CoO, in which H2 molecule is activated on Co0 and EL is strongly adsorbed on CoO via hydroxyl groups. [ABSTRACT FROM AUTHOR]

Phylogeography documents the spatial distribution of genetic lineages that result from demographic processes, such as population expansion, population contraction, and gene movement, shaped by climate fluctuations and the physical landscape. Because most phylogeographic studies have used neutral markers, the role of selection may have been undervalued. In this paper, we contend that plants provide a useful evolutionary lesson about the impact of selection on spatial patterns of neutral genetic variation, when the environment affects which individuals can colonize new sites, and on adaptive genetic variation, when environmental heterogeneity creates divergence at specific loci underlying local adaptation. Specifically, we discuss five characteristics found in plants that intensify the impact of selection: sessile growth form, high reproductive output, leptokurtic dispersal, isolation by environment, and the potential to evolve longevity. Collectively, these traits exacerbate the impact of environment on movement between populations and local selection pressures-both of which influence phylogeographic structure. We illustrate how these unique traits shape these processes with case studies of the California endemic oak, Quercus lobata, and the western North American lichen, Ramalina menziesii Obviously, the lessons we learn from plant traits are not unique to plants, but they highlight the need for future animal, plant, and microbe studies to incorporate its impact. Modern tools that generate genome-wide sequence data are now allowing us to decipher how evolutionary processes affect the spatial distribution of different kinds of genes and also to better model future spatial distribution of species in response to climate change.

The rich physical properties unveiled in a plethora of transition and rare-earth metal oxides have been attributed to the intricate interplays between the orbital, charge, and spin degrees of freedom. Among them, rare-earth manganites (RMnO3) have been attracting tremendous attention owing to the ionic size-induced lattice distortion dictated by the Goldschmidt tolerance factor and the substantial Jahn–Teller distortion unique to Mn3+ ions, which evidently have resulted in a variety of emergent characteristics in electronic, magnetic, and orbital ordering. In this work, we deliberately engineered the orientation of a series of orthorhombic YMnO3 (o-YMO) films grown on SrTiO3(100) [STO(100)] and SrTiO3(110) [STO(110)] substrates by means of pulsed laser deposition. The x-ray diffraction (XRD) and reciprocal space mapping revealed that o-YMO/STO(100) is c-axis-oriented and o-YMO/STO(110) is a-axis-oriented, respectively. The XRD ϕ-scans further indicate that both films have excellent in-plane crystallinity, allowing the exploration of anisotropies along the respective crystallographic orientations. Indeed, the x-ray absorption linear dichroism spectroscopy taken along the respective crystallographic orientations evidently exhibited substantial anisotropy. Theoretical fitting with configuration interaction cluster calculations suggests that the d 3 z 2 − r 2 orbitals are parallel to YMO[001]/(100), leading to stronger electron scattering along the c-axis. Independent polarization-dependent Δ R/R spectra obtained using the femtosecond pump–probe method exhibited substantial anisotropic behaviors in carrier relaxation dynamics when probing along different crystallographic orientations, presumably due to orbital ordering anisotropies. [ABSTRACT FROM AUTHOR]